Students need to come up with explanations for why a person cannot distinguish between three apples of different colors and find engineering solutions. As a first step, students need to identify what they know and what they need to know in order to solve this problem. In the classic version of this unit, a worksheet is handed to the students, then they form groups discussing their ideas before a class discussion which pinpoints ideas related to:
- properties of light and light spectrum
- waves and wave-properties of light
- structure of the eye
Instead of writing down unstructured ideas, students can create mind maps based on questions. After a moderate amount of research online, they can pinpoint areas they need information about. They can share their mind-maps and complete them, then share them with the teacher.
After a short lecture on the wave-properties of light, students draw their own waves and analyse their characteristics. They then learn about the speed of light in different medium (refraction) as well as simple reflection.
Google Spreadsheet
Using a spreadsheet, students can experiment with different frequencies and see how it affect wavelength. This spreadsheet can include electromagnetic properties such as the speed of light.
In this lesson students learn about how light is absorbed and reflected by objects. Using the properties of refraction as stated in the last lesson, they will find the propagation of light of different colors (rainbows). Essentially, students need to understand single slit diffraction.
Photo-sharing website / camera app
Using a diffraction grating, students take pictures of different light sources using their cellphones. They can then share their pictures and realize that different colors of light are diffracted at different angles. Using the single slit formula, they can measure this angle for different wavelength.
There is no particular app for this assignment - just a camera to take pictures of the light emission of different colors of light.
Inventing a solution for a color-blind person
This last part asks for students to come up with solutions for a color blind person - not to make her see colors, but find a tool that would allow her to differentiate between two different colors. Diffraction gradients and light sources are provided, they only need to build a simple device. They can experiment and present their device in class.
Prezi
Make a presentation of the physics behind their invention, how their device work and pictures proving that it works. I do not have an example - I don't have diffraction gratings.
Presenting an invention using an engaging presentation tool is a pretext to review and apply all the concepts that have been learnt.
Electromagnetic Waves
Unit of study from Research Experiences for Teachers (RET) in Engineering and Computer Science
The Three Color Mystery
Students need to come up with explanations for why a person cannot distinguish between three apples of different colors and find engineering solutions. As a first step, students need to identify what they know and what they need to know in order to solve this problem. In the classic version of this unit, a worksheet is handed to the students, then they form groups discussing their ideas before a class discussion which pinpoints ideas related to:- properties of light and light spectrum
- waves and wave-properties of light
- structure of the eye
Waves and wave-properties
After a short lecture on the wave-properties of light, students draw their own waves and analyse their characteristics. They then learn about the speed of light in different medium (refraction) as well as simple reflection.Light
In this lesson students learn about how light is absorbed and reflected by objects. Using the properties of refraction as stated in the last lesson, they will find the propagation of light of different colors (rainbows). Essentially, students need to understand single slit diffraction.Inventing a solution for a color-blind person
This last part asks for students to come up with solutions for a color blind person - not to make her see colors, but find a tool that would allow her to differentiate between two different colors. Diffraction gradients and light sources are provided, they only need to build a simple device. They can experiment and present their device in class.References
Ellen Zielinski, Courtney Faber, Marissa H. Forbes, through Clemson University's "Engineering Fibers and Films Experience – EFF-X" Research Experience for Teachers Program, National Science Foundation grant no. EEC-0602040retrieved at: __http://www.teachengineering.org/view_curricularunit.php?url=collection/clem_/curricular_units/clem_waves_unit/clem_waves_unit.xml#contents__